1. Field of the Invention
The invention relates generally to tools and systems for wood frame building construction, or for other building construction that uses metal, polymer, concrete or composite members in techniques similar to traditional wood frame construction. More specifically, the invention relates to a construction system that comprises a laser light unit that may be used to accurately construct a roof, walls, and other portions of a building. The invented laser light unit may be used, preferably with invented cutting guides and/or targets and/or laser prisms, to replace construction techniques that use chalk and dry lines, rulers and squares, and other conventional tools. For example, the invented apparatus and methods may be used to accurately construct pony walls, and/or to straighten stud frame walls that tend to bend and curve due to their long length. The invented apparatus and methods may be used to accurately set trusses and construct a hip roof or other stepped truss roof. The invented apparatus and methods may be used to accurately connect one roof to another, such as in a roof over-build project. Also, for example, the invented apparatus and methods may be used to cut an accurate roof overhang to result in “non-wavy” fascia. A combination of one or more laser units, prisms, and targets may be used for building layout without chalk or dry lines.
2. Related Art
Laser levels have been designed that utilize the tendency of a laser light to travel a great distance in a straight line. Such levels have been used to indicate a point a great distance from the laser source that is at the same height as the laser source. Such a laser level may be used, for example, to “mark” with light a spot on a distant wall or foundation that is equal in elevation to a reference point on another wall or foundation.
Some laser systems have been developed that emit light in various directions and/or in various planes. The patent literature includes: Jan, et al. U.S. Pat. No. 6,163,969, issued Dec. 26, 2000; Waibel U.S. Pat. No. 6,754,969, issued Jun. 29, 2004; U.S. Pat. No. 6,829,834, issued Dec. 14, 2004; Turner U.S. Pat. No. 6,834,435, issued Dec. 28, 2004; Raskin, et al. U.S. Pat. No. 6,914,930, issued Jul. 5, 2005; Sergyeyenko, et al. U.S. Pat. No. 6,964,106, issued Nov. 15, 2005; Marshall, et al. U.S. Pat. No. 7,031,367, published Apr. 18, 2006; Heger, at al. U.S. Pat. No. 7,181,853, issued Feb. 27, 2007; Goodrich U.S. Pat. No. 7,287,336, issued Oct. 30, 2007; Levine, et al. US2005/0155238, published Jul. 21, 2005; Nash US 2005/0283987, published Dec. 29, 2005; Krantz, et al. U.S. 2006/0059699, published Mar. 23, 2006; and Hersey, et al. US 2007/0271800, published Nov. 29, 2007. Radke, et al U.S. Pat. No. 6,732,439, issued May 11, 2004 discloses a wall-form aligning tool that may be threadably attached to a horizontal platform that is clamped to one corner of a form for pouring of concrete. The Radke, et al. aligning tool may include a laser-emitting device for hitting a target clamped to another corner of the form that is distanced from the aligning tool; the laser is reported to assist in construction of the concrete wall forms in a straight line between said form corners.
Several multi-function tools have been developed, some of which include laser-emitting devices. For example, Hitchcock U.S. Pat. No. 6,839,974, issued Jan. 11, 2005, discloses a “Multi-function Layout Square with Laser” that includes an elongated casing and a protractor plate. The elongated casing is reported to be useable as a level, a plumb bob, a ruler, and a compass. The combined casing and protractor plate tool is reported to be usable as a framing square or rafter square and/or gauge or scribe for straight lines, arcs, or circles. Diaz, et al. US 2007/0011896, published Jan. 18, 2007 discloses a “Multi-Purpose Tool” that comprises two, elongated, parallel “extensions” that are pivotally connected at their ends. The tool is reported to be usable for measuring length, angles, pitch, or a combination of these measurements.
Various tools, comprising elongated, parallel members that are pivotal relative to each other, have been developed that are reported to be usable for roof rafter measurement and/or marking. Kook, et al. U.S. Pat. No. 5,452,522, issued Sep. 26, 1995, discloses a “Calibrated Bevel Square with Integrated Electronic Level and Plumb” that comprises two squares each with two legs or blades 90 degrees apart, wherein a first of the squares does not have a level, and the second of the squares does include an electronic level. The squares are pivotally attached at their vertices by a pivot pin. The tool may be used to measure the inclination of an existing rafter by resting the first square on or under the rafter, and moving the second square relative to the first square until the second square indicates that it is level. The resulting angle between the two squares may be read by referring to indicia on the tool, said angle being indicative of the rafter pitch. Moore U.S. Pat. No. 6,725,555, issued Apr. 27, 2004, discloses a pivoting rafter square for laying out rafters that also comprises two squares, wherein a first square may be laid on or under a rafter and the second square may be pivoted and fixed with its legs horizontal and vertical. The relationship between the two squares may be read from one of the square's indicia that are pointed to by the other square, thus, indicating the pitch of the rafter. May U.S. Pat. No. 6,796,046, issued Sep. 28, 2004, discloses a “Miter Cut, Plumb Cut, and Seat Cut Angle Finding System” that includes two parallel blades that are pivotal relative to each other and wherein the angle between may be read by referring to indicia provided near the pivot point. Casner, et al. U.S. Pat. No. 7,243,436, issued Jul. 17, 2007, discloses a “T-Bevel Plumb Tool” for identifying and placing a plumb line. The tool comprises two parallel blades that are pivotal relative to each other, wherein a first blade may be placed on a rafter, and the second blade, having a level, may be pivoted to plumb. The second blade may be used as a straight-edge for marking a plumb line on the rafter.
To mark or visualize a line, in wood frame construction, between one or more spaced members, or along a long member, common methods of construction use chalk lines and/or dry lines. For example, when a rafter/truss roof overhang is to be cut prior to application of fascia, a chalk line is held and snapped across many rafters, transverse to the length of the rafters. Such a chalk line, if handled expertly and in calm weather, may produce a chalk mark on each rafter that generally indicates the amount of the rafter that should be cut off. Such a chalk line, if handled in-expertly and/or in windy weather, may produce inaccurate, irregular marks, wherein the rafters can end up being cut to different lengths or wherein the builder has to proceed slowly to try to estimate and correct the inaccuracies. Sawing off the ends of rafters based on the chalk line marks, and/or based on a pencil mark from use of a prior art square, can be called an “estimated” saw line at best.
Likewise, a dry line is prone to error and inaccuracy, especially if stretched/pulled a great distance. Using a dry line high up in the air and/or in windy weather, and/or on wet, snow or ice-covered surfaces, can be frustrating, slow, and even more inaccurate than a chalk line.
There is a need for improved tools and/or methods of wood frame construction (and/or for other building frame construction using metal, polymer, concrete, or concrete), to replace methods that mainly utilize chalk lines and dry lines, pencil-marking along squares and rulers, and “estimated” sawing along said chalk lines or pencil-mark lines. There is a need for a system that involves minimum or no estimation when building an overbuild roof. There is a need for a system that can increase the accuracy and speed of roof and/or wall construction, in general, and that does so with a minimum of equipment. As will be described in the following Summary and Detailed Description, the preferred apparatus and methods comprise a laser unit and cooperating tools selected from cutting guides, targets, and/or prisms, depending upon the frame construction application. The preferred embodiments greatly increase the speed and accuracy of pony wall and wall construction, truss setting and hip/stepped-truss roof construction, roof overbuilding, truss tail cutting, and building layout, wherein the invented laser light unit and cooperating accessory items are easily portable and easily usable in a variety of frame construction applications.